Switch voltage stabilizing circuit with frequency spectrum shaping function and method

Abstract

The invention discloses a switch voltage stabilizing circuit with a frequency spectrum shaping function and a method, aiming at reducing electromagnetic interference; the circuit comprises an energy storage element which can store the energy; a switch which is electrically coupled to the energy storage element, when the switch is conducted, the energy storage element stores the energy, when the switch is opened, the stored energy in the energy storage element can be conveyed to the load; a current sample circuit which is electrically coupled to the switch for sampling the current passing through the switch and generating current sample signals of the current passing through the switch; a voltage feedback circuit which samples the output voltage of the switch voltage stabilizing circuit and generates the feedback signals relative to the output voltage of the switch voltage stabilizing circuit; a control circuit which controls the on and off of the switch according to the current sample signals and the feedback signals; and a frequency spectrum shaping circuit which is electrically coupled to the control circuit for adjusting the frequency of on and off of the switch.

Description

technical field [0001] The invention relates to a switching voltage stabilizing circuit, in particular to a switching voltage stabilizing circuit and a method with spectrum shaping function. Background technique [0002] Many electronic devices today require DC voltage to be powered, and this DC supply voltage usually comes from an adapter. The adapter obtains AC voltage from the wall socket (grid), converts the AC voltage into an uncontrolled DC voltage through a rectifier bridge, and converts the uncontrolled DC voltage into the required DC power supply voltage through a switching power supply. [0003] Switching power supplies usually use transformers or inductors as energy storage elements. For example, a transformer is used as an energy storage element in a flyback converter. A switch is electrically coupled to the primary side of the transformer, and the control circuit controls the switch to be turned on and off, so that energy is alternately stored or transmitted in...

AI Technical Summary

Problems solved by technology

[0005] The existing method of reducing electromagnetic interference is to add absorption circuit and input filter circuit in the switching power supply to reduce the pollution to the power grid, but this method inevitably increases the complexity of the circuit design and increases the volume of the switching power supply , weight and cost

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